The northern west coast was hit by a series of tidal waves following a massive earthquake off the northern coast of Sumatra at 9am this morning. Unconfirmed reports put the death toll at least 15.

According to an eye witness, the 30-foot waves hit Penang northern beaches around 1.45pm.

"At first it looked like a thin white line in the distance, just above the horizon," said Dr Jacob George, who witnessed the incident from the Casurina Beach Hotel, on Batu Ferringghi beach.

"As it approached us, we could hear roaring sound coming from behind the wave. It quickly grew louder. That was when a few navy personal nearby realized that it was a tidal wave and told people to leave the beach area. A few seconds later, the wave hit, sending water all the way into the hotel lobby."

Dr George described the whole incident as "quite frightening". He described the current scene to be chaotic, with the sirens of emergency vehicles zooming up and down the coastal road, constantly in the background.

Dr George questioned why there was no warning issued by the authorities. "The earthquake happened at 9am, yet there was no warning given to stay off the beaches," he said.

Tidal waves also hit Kedah and Langkawi. The Star has reported 5 deaths in Kota Kuala Muda.

Tidal waves swept through the Indian Ocean, causing massive casualties along coastal areas from Sri Lanka to Phuket. Media reports have put death tolls in India and Sri Lanka at over 1,000 each, with 200 dead in Indonesia and 61 in Thailand. With hundreds still missing, the toll is expected to rise.

The quake with a magnitude of 8.9 is the strongest earthquake in the last 40 years, and the fifth-largest since 1900. It also comes just two days after an 8.1 magnitude earthquake struck 800 km south of Tasmania.